How is it possible to fire the same intermediate timer event multiple times

I modeled a loop within my process that should periodically check, whether or not the proper information has been put into the DB (polling mechanism). For this reason, I have connected a start event with a intermediate timer event (Duration PT5S), the timer event is connected with a service task (for the check), the service task is connected with a XOR gateway (complete yes/no). One path of the XOR goes back to the timer event.

However, the timer seems to be fired only one time. I guess the counter has not been reset by the process engine. Is there a way to realize that?